This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A379095 #6 Dec 20 2024 12:42:38 %S A379095 3,3,3,3,3,3,3,3,3,3,3,5,3,3,5,3,3,3,3,15,5,3,3,3,3,5,3,5,9,3,5,3,5,3, %T A379095 3,7,9,5,3,15,3,5,7,3,3,7,3,3,5,5,15,3,9,7,15,3,5,3,5,3,9,5,21,5,3,7, %U A379095 3,3,5,3,15,3,5,5,9,7,3,7,21,9,5,3,15,5 %N A379095 The water sealings of numbers that are not waterproof (A379097). %C A379095 The water sealing of a number n is the smallest positive integer s(n) so that the water hull of n can be written h(n) = n * s(n). n is waterproof if and only if s(n) = 1. %e A379095 48300 has a water capacity of 17 and so is not waterproof. The waterproof hull of 48300 is 1014300. Thus the sealing of 48300 is 21. The prime factorization of the sealing shows where the water holes of n are, in this example at 3 and 7 (see the example in A275339). %o A379095 (Python) %o A379095 # Using function "WaterCapacity" from A275339. %o A379095 def s(n: int) -> int: %o A379095 j = n %o A379095 while True: %o A379095 if WaterCapacity(j) == 0 and j % n == 0: return j %o A379095 j += n %o A379095 print([s(n)//n for n in range(1, 1200) if WaterCapacity(n) > 0]) %Y A379095 Cf. A275339, A379096, A379097, A379098. %K A379095 nonn %O A379095 1,1 %A A379095 _Peter Luschny_, Dec 16 2024